NutriDex

The Supplement Research Compendium
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Jambolan (Jamun / Java Plum)

Syzygium cumini

Anthocyanin-rich tropical plum with antidiabetic folk use

Preliminary evidence 🍎Fruits

✚ Updated · How we grade evidence

Evidence tier
Preliminary
Research weight
Citations
9 verified / 9
Classification
Fruits
❝
What the evidence says. Early or small human trials; promising but not yet conclusive.

Nutrition per serving 1 cup (135 g)

135gSERVING
  • Water 112 g83%
  • Sugars 12.6 g9%
  • Other carbs 8.4 g6%
  • Protein 1 g1%
  • Fat 0.3 g0%
What's in one serving, by weight — average composition (USDA).
Vitamin C21%Potassium2%Magnesium5%Iron1%Calcium2%Vitamin B63%
One serving as % of the adult daily requirement (FDA Daily Values). The bold outer ring = 100% of a day's needs.
81 kcal0.97 g protein0 g fiber0.31 g fat
NutrientPer serving% daily value
Vitamin C19 mg21%
Potassium107 mg2%
Magnesium20 mg5%
Iron0.26 mg1%
Calcium26 mg2%
Vitamin B60.05 mg3%
Sodium19 mg1%

Composition data: USDA FoodData Central ↗

What is Jambolan (Jamun / Java Plum)?

Jambolan (Jamun / Java Plum) (Syzygium cumini) is a fruit used for traditional and preclinical antidiabetic / glucose-lowering activity (largely seed-based; best human rcts of leaf preparations were negative). NutriDex grades the human evidence as Preliminary. Jambolan is widely promoted as an antidiabetic fruit, but the human evidence is far weaker than its reputation. The best-controlled clinical trials used leaf tea/extract and were negative: a randomized, double-blind, double-dummy trial in 27 type 2 diabetics (Teixeira 2006) found S. cumini tea produced no change in fasting glucose, while glyburide lowered it significantly; an earlier randomized controlled trial by the same group (Teixeira 2004) reached the same conclusion. Most positive data come from seed (not pulp) powder studies and from rodent and in-vitro models, where anthocyanins and tannins show alpha-glucosidase/alpha-amylase inhibition, antioxidant, and lipid-lowering activity. A small open-label seed-powder trial (cited in Rizvi 2022) reported modest improvements in glycemia and dyslipidemia, but such studies are underpowered, short, and often co-administered with standard drugs. The fruit itself is a low-calorie source of vitamin C and potassium plus pigment polyphenols. Note that USDA SR Legacy does not report sugar or dietary fiber for this item, so its fiber content is unquantified in the reference database. Overall the weight of human evidence is preliminary and mixed, and rigorous, adequately powered RCTs of standardized preparations are still lacking.

Purported Benefits

✓Traditional and preclinical antidiabetic / glucose-lowering activity (largely seed-based; best human RCTs of leaf preparations were negative)
✓Antioxidant capacity from anthocyanins and polyphenols (mostly in-vitro)
✓Lipid-lowering / cardiometabolic signals in small human and animal studies
✓Anti-inflammatory activity in vitro and in rodent models
✓Astringent gastrointestinal use for diarrhea and digestive complaints (traditional)
✓Low-calorie source of vitamin C and potassium

Dosing & Compounds

Typical Dose
Culinary: ~100-135 g fresh fruit (1 cup). Studied antidiabetic preparations typically use seed powder (~5-10 g/day) rather than fresh pulp; benefits cannot be assumed from eating the fruit.
Active Compounds
Anthocyanins (delphinidin-, malvidin-, petunidin-, cyanidin-3,5-diglucosides)Hydrolyzable tannins / ellagitannins (gallic acid, ellagic acid)Flavonols (quercetin, rutin, myricetin)Phenolic acids (gallic, chlorogenic, ferulic acids)Seed alkaloid jambosine and glycoside jambolin (antimellin)Triterpenoids including oleanolic acidVitamin C (ascorbic acid)Minerals: potassium, magnesium, iron

Safety & Cautions

Generally safe as a food. Concentrated seed/extract preparations may have additive hypoglycemic effects with insulin or sulfonylureas, so diabetics combining them with medication should monitor blood glucose to avoid hypoglycemia. High tannin content is astringent and may reduce absorption of iron and some drugs; very large amounts may cause GI upset or constipation. Safety of medicinal doses in pregnancy and lactation is not established. The hard seed is a choking hazard and is not eaten whole. Educational only — always check with your doctor or pharmacist before combining Jambolan (Jamun / Java Plum) with any medicine.

Key Studies

Food composition database USDA SR Legacy (169913) ✓ Source
Java-plum (jambolan), raw, per 100 g: 60 kcal, 15.56 g carbohydrate, 0.72 g protein, 0.23 g fat, 14.3 mg vitamin C, 79 mg potassium; sugar and dietary fiber are not reported in this record.
RCT Teixeira 2004 ✓ PubMed
Randomized double-blind double-dummy controlled trial: S. cumini leaf preparation produced no improvement in glycemic control in type 2 diabetes; concluded no hypoglycemic effect.
RCT Teixeira 2006 ✓ PubMed
RCT in 27 type 2 diabetics: fasting glucose fell significantly with glyburide but did not change with S. cumini leaf tea or placebo; leaf-tea folk remedy ineffective.
Narrative review Rizvi 2022 ✓ Full text
Review (Molecules): cites a 99-patient trial in which 10 g jamun seed powder twice daily improved sugar levels and dyslipidemia over 90 days; documents anthocyanin and tannin bioactivity.
Review Qamar 2022 ✓ Full text
Comprehensive review (Foods) of S. cumini phytochemistry: identifies anthocyanin 3,5-diglucosides (delphinidin, malvidin, petunidin), tannins, and jambosine/jambolin as bioactives with antidiabetic and antioxidant actions.
Experimental Pandey 2025 ✓ Full text
Plants (Basel) study: S. cumini seed extracts (methanolic kernel most active) demonstrated antioxidant, xanthine-oxidase-inhibitory, and antibacterial activity in vitro, attributed to phenolic/tannin content.
Experimental Abdin 2020 ✓ Source
Anthocyanin di-glucosides (delphinidin-, petunidin-, malvidin-3,5-diglucoside) isolated from S. cumini pulp showed strong antioxidant activity; malvidin diglucoside inhibited NO, IL-6, IL-1B and TNF-alpha in LPS-stimulated macrophages.
Experimental El-Nashar 2021 ✓ Full text
GC/MS and enzyme-inhibition study (Molecules) of S. cumini leaf essential oil documented alpha-amylase (IC50 ~57.8 ug/mL) and moderate alpha-glucosidase inhibitory activity, supporting a carbohydrate-digestion-slowing mechanism.
Experimental Ahmed 2019 ✓ Full text
PLoS One study: S. cumini leaf extract is high in total phenolics/flavonoids and showed antioxidant, cytoprotective and anti-inflammatory activity in vitro and in vivo.
9 sources cited · 9 verified Search all studies on PubMed ↗

Common questions about Jambolan (Jamun / Java Plum)

What is Jambolan (Jamun / Java Plum) used for?

Jambolan (Jamun / Java Plum) is most often taken for Traditional and preclinical antidiabetic / glucose-lowering activity (largely seed-based; best human RCTs of leaf preparations were negative), Antioxidant capacity from anthocyanins and polyphenols (mostly in-vitro), Lipid-lowering / cardiometabolic signals in small human and animal studies, Anti-inflammatory activity in vitro and in rodent models. Anthocyanin-rich tropical plum with antidiabetic folk use

Does Jambolan (Jamun / Java Plum) work — what does the evidence say?

Preliminary evidence. Early or small human trials; promising but not yet conclusive. Jambolan is widely promoted as an antidiabetic fruit, but the human evidence is far weaker than its reputation. The best-controlled clinical trials used leaf tea/extract and were negative: a randomized, double-blind, double-dummy trial in 27 type 2 diabetics (Teixeira 2006) found S. cumini tea produced no change in fasting glucose, while glyburide lowered it significantly; an earlier randomized controlled trial by the same group (Teixeira 2004) reached the same conclusion. Most positive data come from seed (not pulp) powder studies and from rodent and in-vitro models, where anthocyanins and tannins show alpha-glucosidase/alpha-amylase inhibition, antioxidant, and lipid-lowering activity. A small open-label seed-powder trial (cited in Rizvi 2022) reported modest improvements in glycemia and dyslipidemia, but such studies are underpowered, short, and often co-administered with standard drugs. The fruit itself is a low-calorie source of vitamin C and potassium plus pigment polyphenols. Note that USDA SR Legacy does not report sugar or dietary fiber for this item, so its fiber content is unquantified in the reference database. Overall the weight of human evidence is preliminary and mixed, and rigorous, adequately powered RCTs of standardized preparations are still lacking.

What is the typical dose of Jambolan (Jamun / Java Plum)?

Culinary: ~100-135 g fresh fruit (1 cup). Studied antidiabetic preparations typically use seed powder (~5-10 g/day) rather than fresh pulp; benefits cannot be assumed from eating the fruit.

Is Jambolan (Jamun / Java Plum) safe? Any cautions or side effects?

Generally safe as a food. Concentrated seed/extract preparations may have additive hypoglycemic effects with insulin or sulfonylureas, so diabetics combining them with medication should monitor blood glucose to avoid hypoglycemia. High tannin content is astringent and may reduce absorption of iron and some drugs; very large amounts may cause GI upset or constipation. Safety of medicinal doses in pregnancy and lactation is not established. The hard seed is a choking hazard and is not eaten whole.

How many studies support Jambolan (Jamun / Java Plum)?

NutriDex cites 9 sources for Jambolan (Jamun / Java Plum), graded "Preliminary".

Cite this page
APA

Peh, D. (2026). Jambolan (Jamun / Java Plum) (Syzygium cumini): Benefits, Dosage, Side Effects & Evidence. NutriDex — The Supplement Research Compendium. Retrieved 26 Jun 2026, from https://nutridex.info/s/jambolan-syzygium-cumini

BibTeX
@misc{nutridex_jambolan_syzygium_cumini,
  author       = {Peh, Daryl},
  title        = {Jambolan (Jamun / Java Plum) (Syzygium cumini): Benefits, Dosage, Side Effects \& Evidence},
  year         = {2026},
  howpublished = {NutriDex --- The Supplement Research Compendium},
  url          = {https://nutridex.info/s/jambolan-syzygium-cumini},
  note         = {Reviewed by Dr Daryl Peh, MBBS Singapore, MMed FM. Accessed 2026-06-26}
}

For medical claims, citing the underlying primary studies linked above is preferred. NutriDex is an educational reference, not medical advice.

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